Bond strength tests of dental adhesive systems and their correlation with clinical results : a meta-analysis

OBJECTIVE: To evaluate the variability of bond strength test results of adhesive systems (AS) and to correlate the results with clinical parameters of clinical studies investigating cervical restorations. MATERIALS AND METHODS: Regarding the clinical studies, the internal database which had previously been used for a meta-analysis on cervical restorations was updated with clinical studies published between 2008 and 2012 by searching the PubMed and SCOPUS databases. PubMed and the International Association for Dental Research abstracts online were searched for laboratory studies on microtensile, macrotensile and macroshear bond strength tests. The inclusion criteria were (1) dentin, (2) testing of at least four adhesive systems, (3) same diameter of composite and (4) 24h of water storage prior to testing. The clinical outcome variables were retention loss, marginal discoloration, detectable margins, and a clinical index comprising the three parameters by weighing them. Linear mixed models which included a random study effect were calculated for both, the laboratory and the clinical studies. The variability was assessed by calculating a ratio of variances, dividing the variance among the estimated bonding effects obtained in the linear mixed models by the sum of all variance components estimated in these models. RESULTS: Thirty-two laboratory studies fulfilled the inclusion criteria comprising 183 experiments. Of those, 86 used the microtensile test evaluating 22 adhesive systems (AS). Twenty-seven used the macrotensile test with 17 AS, and 70 used the macroshear test with 24 AS. For 28 AS the results from clinical studies were available. Microtensile and macrotensile (Spearman rho=0.66, p=0.007) were moderately correlated and also microtensile and macroshear (Spearman rho=0.51, p=0.03) but not macroshear and macrotensile (Spearman rho=0.34, p=0.22). The effect of the adhesive system was significant for microtensile and macroshear (p<0.001) but not for macrotensile. The effect of the adhesive system could explain 36% of the variability of the microtensile test, 27% of the macrotensile and 33% of the macroshear test. For the clinical trials, about 49% of the variability of retained restorations could be explained by the adhesive system. With respect to the correlation between bond strength tests and clinical parameters, only a moderate correlation between micro- and macrotensile test results and marginal discoloration was demonstrated. However, no correlation between these tests and a retention loss or marginal integrity was shown. The correlation improved when more studies were included compared to assessing only one study. SIGNIFICANCE: The high variability of bond strength test results highlights the need to establish individual acceptance levels for a given test institute. The weak correlation of bond-strength test results with clinical parameters leads to the conclusion that one should not rely solely on bond strength tests to predict the clinical performance of an adhesive system but one should conduct other laboratory tests like tests on the marginal adaptation of fillings in extracted teeth and the retention loss of restorations in non-retentive cavities after artificial aging.

Soil carbon and nitrogen mineralization under different tillage systems and Permanent Groundcover cultivation between Orange trees

The objective of this work was to evaluate the alterations in carbon and nitrogen mineralization due to different soil tillage systems and groundcover species for intercropped orange trees. The experiment was established in an Ultisol soil (Typic Paleudults) originated from Caiuá sandstone in northwestern of the state of Paraná, Brazil, in an area previously cultivated with pasture (Brachiaria humidicola). Two soil tillage systems were evaluated: conventional tillage (CT) in the entire area and strip tillage (ST) with a 2-m width, each with different groundcover vegetation management systems. The citrus cultivar utilized was the 'Pera' orange (Citrus sinensis) grafted onto a 'Rangpur' lime rootstock. The soil samples were collected at a 0-15-cm depth after five years of experiment development. Samples were collected from under the tree canopy and from the inter-row space after the following treatments: (1) CT and annual cover crop with the leguminous Calopogonium mucunoides; (2) CT and perennial cover crop with the leguminous peanut Arachis pintoi; (3) CT and evergreen cover crop with Bahiagrass Paspalum notatum; (4) CT and cover crop with spontaneous B. humidicola grass vegetation; and (5) ST and maintenance of the remaining grass (pasture) of B. humidicola. The soil tillage systems and different groundcover vegetation influenced the C and N mineralization, both under the tree canopy and in the inter-row space. The cultivation of B. humidicola under strip tillage provided higher potential mineralization than the other treatments in the inter-row space. Strip tillage increased the C and N mineralization compared to conventional tillage. The grass cultivation increased the C and N mineralization when compared to the others treatments cultivated in the inter-row space.

Diet-related buccal dental microwear patterns in central african pygmy foragers and bantu-speaking farmer and pastoralist populations.

Pygmy hunter-gatherers from Central Africa have shared a network of socioeconomic interactions with non-Pygmy Bantu speakers since agropastoral lifestyle spread across sub-Saharan Africa. Ethnographic studies have reported that their diets differ in consumption of both animal proteins and starch grains. Hunted meat and gathered plant foods, especially underground storage organs (USOs), are dietary staples for pygmies. However, scarce information exists about forager-farmer interaction and the agricultural products used by pygmies. Since the effects of dietary preferences on teeth in modern and past pygmies remain unknown, we explored dietary history through quantitative analysis of buccal microwear on cheek teeth in well-documented Baka pygmies. We then determined if microwear patterns differ among other Pygmy groups (Aka, Mbuti, and Babongo) and between Bantu-speaking farmer and pastoralist populations from past centuries. The buccal dental microwear patterns of Pygmy hunter-gatherers and non-Pygmy Bantu pastoralists show lower scratch densities, indicative of diets more intensively based on nonabrasive foodstuffs, compared with Bantu farmers, who consume larger amounts of grit from stoneground foods. The Baka pygmies showed microwear patterns similar to those of ancient Aka and Mbuti, suggesting that the mechanical properties of their preferred diets have not significantly changed through time. In contrast, Babongo pygmies showed scratch densities and lengths similar to those of the farmers, consistent with sociocultural contacts and genetic factors. Our findings support that buccal microwear patterns predict dietary habits independent of ecological conditions and reflect the abrasive properties of preferred or fallback foods such as USOs, which may have contributed to the dietary specializations of ancient human populations.

Evaluation of the indication for surgical extraction of third molars according to the oral surgeon and the primary care dentist. Experience in the Master of Oral Surgery and Implantology at Barcelona University Dental School

Introduction: Third molar extraction is the most frequent procedure in oral surgery. The present study evaluates the indication of third molar extraction as established by the primary care dentist (PCD) and the oral surgeon, and compares the justification for extraction with the principal reason for patient consultation. Patients and method: A descriptive study was made of 319 patients subjected to surgical removal of a third molar in the context of the Master of Oral Surgery and Implantology (Barcelona University Dental School, Barcelona, Spain) between July 2004 and March 2005. The following parameters were evaluated: sex, age, molar, type of impaction, position according to the classifications of Pell and Gregory and of Winter, and the reasons justifying extraction. Results: The lower third molars were the most commonly extracted molars (73.7%). A total of 69.6% of the teeth were covered by soft tissues only. Fifty-six percent of the lower molars corresponded to Pell and Gregory Class IIB, while 42.1% were in the vertical position. The most common reason for patient reference to our Service of Oral Surgery on the part of the PCD was prophylactic removal (51.0% versus 46.1% in the case of the oral surgeon). Discussion and conclusions. Our results show prophylaxis to be the principal indication of third molar extraction, followed by orthodontic reasons. Regarding third molars with associated clinical symptoms or signs, infectious disease-including pericoronitis- was the pathology most often observed by the oral surgeon, followed by caries. This order of frequency was seen to invert in the case of third molars referred for extraction by the PCD. A vertical position predominated among the third molars with associated pathology

Morphological, hydrological, biogeochemical and ecological changes and challenges in river restoration - the Thur River case study

River restoration can enhance river dynamics, environmental heterogeneity and biodiversity, but the underlying processes governing the dynamic changes need to be understood to ensure that restoration projects meet their goals, and adverse effects are prevented. In particular, we need to comprehend how hydromorphological variability quantitatively relates to ecosystem functioning and services, biodiversity as well as ground-and surface water quality in restored river corridors. This involves (i) physical processes and structural properties, determining erosion and sedimentation, as well as solute and heat transport behavior in surface water and within the subsurface; (ii) biogeochemical processes and characteristics, including the turnover of nutrients and natural water constituents; and (iii) ecological processes and indicators related to biodiversity and ecological functioning. All these aspects are interlinked, requiring an interdisciplinary investigation approach. Here, we present an overview of the recently completed RECORD (REstored CORridor Dynamics) project in which we combined physical, chemical, and biological observations with modeling at a restored river corridor of the perialpine Thur River in Switzerland. Our results show that river restoration, beyond inducing morphologic changes that reshape the river bed and banks, triggered complex spatial patterns of bank infiltration, and affected habitat type, biotic communities and biogeochemical processes. We adopted an interdisciplinary approach of monitoring the continuing changes due to restoration measures to address the following questions: How stable is the morphological variability established by restoration? Does morphological variability guarantee an improvement in biodiversity? How does morphological variability affect biogeochemical transformations in the river corridor? What are some potential adverse effects of river restoration? How is river restoration influenced by catchment-scale hydraulics [GRAPHICS] and which feedbacks exist on the large scale? Beyond summarizing the major results of individual studies within the project, we show that these overarching questions could only be addressed in an interdisciplinary framework.

Diagonal ear lobe crease and atherosclerosis: a review of the medical literature and dental implications

In Spain a significant number of individuals die from atherosclerotic disease of the coronary and carotid arteries without having classic risk factors and prodromal symptoms. The diagonal ear lobe crease (DELC) has been characterized in the medical literature as a surrogate marker which can identify high risk patients having occult atherosclerosis. This topic however has not been examined in either the medical or dental literature emanating from Spain. The majority of clinical, angiography and postmortem reports support the premise that DELC is a valuable extravascular physical sign able to distinguish some patients at risk of succumbing to atherosclerosis of the coronary arteries. A minority of studies have however failed to support this hypothesis. More recently reports using B mode ultrasound have also linked DELC to atherosclerosis of the carotid artery and another report has related DELC to the presence of calcified carotid artery atheromas on panoramic radiographs. DELC is readily visible during head and neck cancer screening examinations. In conjunction with the patient"s medical history, vital signs, and panoramic radiograph, the DELC may assist in atherosclerotic risk assessment

Computer-aided system for morphometric mandibular index computation (Using dental panoramic radiographs)

Objective: We propose and validate a computer aided system to measure three different mandibular indexes: cortical width, panoramic mandibular index and, mandibular alveolar bone resorption index. Study Design: Repeatability and reproducibility of the measurements are analyzed and compared to the manual estimation of the same indexes. Results: The proposed computerized system exhibits superior repeatability and reproducibility rates compared to standard manual methods. Moreover, the time required to perform the measurements using the proposed method is negligible compared to perform the measurements manually. Conclusions: We have proposed a very user friendly computerized method to measure three different morphometric mandibular indexes. From the results we can conclude that the system provides a practical manner to perform these measurements. It does not require an expert examiner and does not take more than 16 seconds per analysis. Thus, it may be suitable to diagnose osteoporosis using dental panoramic radiographs

Buccal dental microwear and stable isotopes of El Collado: A mesolithic site from Spain,

This study examines the correlation between buccal dental microwear and stable isotopes. The buccal surface of post-canine teeth casts from El Collado, the largest Mesolithic site in Spain, were examined under Scanning Electron Microscope; photomicrographs were taken from the middle third of the buccal surface with magnification 100X. Only six individuals passed the criteria for buccal dental microwear analysis. The photomicrographs were treated by adobe Photoshop 8.01 to cover an area 0.56 mm² of middle third of buccal surface, the output photomicrographs were digitized using Sigmascan Pro 5 by SPSS. Then the correlation between buccal microwear pattern and stable isotopes of the same individuals, of the previous study of Guixe et al., 2006, was examined using a Pearson test. Statistical analysis revealed that there is no significant correlation between stable isotopes and buccal dental microwear of the people of the Mesolithic site of El Collado. The historical and archaeological documentation suggest that the Mesolithic people tended to consume marine food. Fish-drying techniques were used during the Mesolithic period which allowed the introduction of dust and sand to the fish. These abrasive particles affected the buccal dental microwear pattern, so that no correlation between the isotopes and microwear may be expected. This also suggests that the buccal dental microwear pattern exceeds dietary reconstruction to reconstruct food processing techniques.

La formació permanent del professorat: la proposta del Ministeri d'Educació i Ciència

L'abril de 1989 el Ministeri d'Educació i Ciencia va presentar a la comunitat educativa un Pla de Formació del Professorat per sis anys que passo a descriure breument. El document pretén ser un marc d'actuació; alhora, descriu el context social i educatiu sobre el qual s'elabora el Pla, del qual deriva un nou perfil del professorat. Així mateix, estableix el que s'anomena «model de formació permanent', que comentaré més endavant. En aquest apartat s'enuncien les concepcions, principis basics i directrius que orienten I'execució del Pla, coherents amb el contingut i les característiques de I'actual reforma del sistema educatiu. Segueix en el document una definició de les estructures de formació, amb un desplegament especial de I'apartat corresponent als centres de professors. A I'apartat «Pla d'Actuació' s'estableixen les finalitats i objectius del PI a, i així mateix les línies d'actuació mitjanyant les quals es pretén atenyer els objectius proposats. Tot seguit s'estableixen els criteris d'avaluació previstos tant per als programes com per al conjunt del Pla. Finalment, es fa una valoració aproximada del cost económic que, tal com s'indica, s'haura d'anar concretant als diferents plans anuals. A continuació, en vint-i-nou annexos, es descriuen les línies generals dels programes que hauran de fer realitat els objectius i els fins que ens proposem.

Complications of guided surgery and immediate loading in oral implantology: a report of 12 cases

Objectives: The growing interest in minimally invasive surgery, together with the possibility of fitting prostheses with immediate function, have led to the development of software capable of planning and manufacturing a surgical guide and prosthesis that can be placed upon conclusion of the implant surgery step. The present study evaluates the surgical and prosthetic complications of implant treatment with the guided surgery technique, together with patient comfort during and after treatment. Patients and methods: A retrospective observational study was made of 19 patients with partially or totally edentulous upper and/or lower maxillae, involving the placement of a total of 122 implants. All cases were planned and operated upon with the guided surgery technique. Results: A total of 122 implants were placed in 14 males and 5 females. The intraoperative surgical complications comprised a lack of primary stability, while the postoperative complications consisted of infections and a lack of implant osteointegration. Ten implants failed. The prosthetic complications in turn comprised loosening of the provisional prosthesis screws, prosthesis tooth fracture, and a lack of passive fit of the immediate prosthesis. The degree of patient satisfaction was evaluated using a verbal scale. Conclusions: Implant restoration with the guided surgery technique and immediate functional loading is a predictable procedure, provided patient selection and the surgical technique are adequate, affording lesser postoperative morbidity and increased patient satisfaction thanks to the immediate restoration of esthetics and function

Retrospective study of 145 supernumerary teeth

Objective: The goal of the present retrospective study is to describe the distribution of the supernumerary teeth in a population of patients that have been attended at the Public Clinic of the Department of Oral Surgery. Background: Supernumerary teeth and multiple hyperdontia are usually associated with different syndromes, such as Gardner syndrome, or with facial fissures; however, they can appear in patients without any pathology. Their prevalence oscillates to 0.5-3.8% in patients with permanent teeth and to 0.35-0.6% in patients with primary teeth. Patients and Methods: A total of 36,057 clinical histories of patients that were admitted at the clinic between September of 1991 and March of 2003 were revised. The following data were extrapolated: age, sex, number of extracted supernumerary teeth, localization, morphology and type of supernumerary teeth. Consequently, 102 patients were included into the present study. Results: Of the 147 supernumerary teeth identified in the oral cavities of patients 145 were extracted. The most frequent supernumerary teeth identified were mesiodens (46.9%), followed by premolars (24.1%) and fourth molars or distal molars (18%). As for location, 74.5% of the supernumerary teeth were found in the superior maxillary bone and 46.9% of the supernumerary teeth were present in the palatine/lingual area. Heteromorphology was found in two thirds of the supernumerary teeth, with conical shape being the most frequent. Finally, 29.7% of the supernumerary teeth had occlusion with permanent teeth, and mesiodens were the predominating type of supernumerary teeth that showed this feature. Conclusions: Mesiodens very frequently cause retention of permanent incisors, which erupt spontaneously after the extraction of supernumerary teeth, if there is sufficient space in the dental arch and if they conserve the eruptive force. Generally, supernumerary premolars are eumorphic and are casually discovered during radiological exam, if not producing any symptomology.

Prevalence of smoking among dentists in Catalonia - Spain (2006). Literature review of smoking cessation practices in the dental office

Objective: The objective of this study was to collect data on the prevalence of smokers among Catalonian dentists (by age and sex) and compare them with existing data on the general population, doctors, registered nurses and pharmacists. The overall prevalence of smokers in Catalonia (2006) was 34.5% of men and 24.3% of women. Data available on the prevalence of smoking among doctors (26.3% men and 22.1% women), pharmacists (19.8% men and 20.6% women) and registered nurses (34.1% men and 35.3% women) relates to the year 2002. Study design: In September 2006, Catalonian dentists (n=3,799) were asked about their habits in relation to tobacco in a self-administered questionnaire, on use and opinions with respect to dental amalgam. Five hundred and seventynine questionnaires were received, of which 538 answered the question on smoking (14.2% of the sample universe). Results: The prevalence of smokers among dentists is lower (24.9% of men and 18.4% of women) than in the general population and other healthcare professionals. In dentists in the age group between 25 and 34 years, the prevalence was 26.1% in men and 14.9% in women, while the prevalence in this age group in the general population was 43.6% and 37.1%, respectively. Conclusion: Catalonian dentists have a much lower prevalence of tobacco use than the general population and lower even than other healthcare professionals. Given that non-smoking healthcare professionals have better awareness for providing recommendations for smoking prevention and cessation, Catalonian dentists may be a valid group for performing this task for which there is scientific evidence.

Verifique sus conocimientos sobre técnicas de diagnóstico por la imagen en patología dental y maxilofacial

Esta entrega, que forma parte de una serie de Nursing sobre las pruebas complementarias, está dedicada a las técnicas de imagen para la exploración dental. La exploración y el diagnóstico se pueden llevar a cabo mediante diferentes modalidades diagnósticas. Las más habituales son la radiología convencional, la tomografía computarizada (TC) y la resonancia magnética (RM). Para facilitar a los profesionales de enfermería los recursos necesarios para satisfacer las demandas de información de los pacientes, es necesario un recorrido por estas técnicas, habituales en los diferentes ámbitos asistenciales. Desde el punto de vista de atención al paciente es útil poder explicar y despejar las dudas que se pudieran plantear respecto a la preparación, a la dinámica y, en general, al proceso diagnóstico.

Verifique sus conocimientos sobre técnicas de diagnóstico por la imagen en patología dental y maxilofacial

Esta entrega, que forma parte de una serie de Nursing sobre las pruebas complementarias, está dedicada a las técnicas de imagen para la exploración dental. La exploración y el diagnóstico se pueden llevar a cabo mediante diferentes modalidades diagnósticas. Las más habituales son la radiología convencional, la tomografía computarizada (TC) y la resonancia magnética (RM). Para facilitar a los profesionales de enfermería los recursos necesarios para satisfacer las demandas de información de los pacientes, es necesario un recorrido por estas técnicas, habituales en los diferentes ámbitos asistenciales. Desde el punto de vista de atención al paciente es útil poder explicar y despejar las dudas que se pudieran plantear respecto a la preparación, a la dinámica y, en general, al proceso diagnóstico.